Bespeco Weeper Mod - 2 transistor?

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.
Post Reply
User avatar
fuzzbuzzfuzz
Breadboard Brother
Information
Posts: 58
Joined: 11 Dec 2009, 14:57
Has thanked: 1 time

Post by fuzzbuzzfuzz »

Hi all, fantastic forum, cheap to great, love it.

Wondered if anyone has a clue how to tame the earache of my Bespesco Weeper and turn it into something more magical (or at least not as shrill, brittle and plain dreadful as it is now!)

There is a thread on here examining a Proel wah and mentioning the Bespeco as the same. However inspired enough to take apart my Bespeco Weeper (and contemplate reverse-engineering it back to Colorsound specs), I notice my board is very different, neat square with 2 BC547C transistors in there....?

Can anyone advise as to which components could be changed (and where they are?) on my Bespeco Weepers PCB (which as you can see is different in layout and in resistor values etc)

Here`s a pic of the inside...

http://fuzzbuzzfuzz.blogspot.com/2011/0 ... -guts.html

Any thoughts are much appreciated :D

That would be very very handy, thanks all!

User avatar
CHEEZOR
Diode Debunker
Information
Posts: 831
Joined: 10 Jul 2009, 18:19
Location: California
Has thanked: 42 times
Been thanked: 50 times

Post by CHEEZOR »

http://fuzzbuzzfuzz.blogspot.com/2011/0
The link isn't working for me.

User avatar
fuzzbuzzfuzz
Breadboard Brother
Information
Posts: 58
Joined: 11 Dec 2009, 14:57
Has thanked: 1 time

Post by fuzzbuzzfuzz »

http://fuzzbuzzfuzz.blogspot.com/2011_0 ... chive.html

:oops: Apologies this one should work! Any thoughts very much appreciated :)

User avatar
CHEEZOR
Diode Debunker
Information
Posts: 831
Joined: 10 Jul 2009, 18:19
Location: California
Has thanked: 42 times
Been thanked: 50 times

Post by CHEEZOR »

fuzzbuzzfuzz wrote:Hi all, fantastic forum, cheap to great, love it.

Wondered if anyone has a clue how to tame the earache of my Bespesco Weeper and turn it into something more magical (or at least not as shrill, brittle and plain dreadful as it is now!)

There is a thread on here examining a Proel wah and mentioning the Bespeco as the same. However inspired enough to take apart my Bespeco Weeper (and contemplate reverse-engineering it back to Colorsound specs), I notice my board is very different, neat square with 2 BC547C transistors in there....?

Can anyone advise as to which components could be changed (and where they are?) on my Bespeco Weepers PCB (which as you can see is different in layout and in resistor values etc)

Here`s a pic of the inside...

http://fuzzbuzzfuzz.blogspot.com/2011/0 ... -guts.html

Any thoughts are much appreciated :D

That would be very very handy, thanks all!
That is definitely not the same circuit that was shown in the other Proel thread. Yours looks VERY similar to a basic Vox/Crybaby circuit. I cant see the component values on some of the components (the ceramic cap, the first band of the resistor right below it, both electrolytic caps, and the diode) I can make some good guesses, but the real values would be better.

I cannot be certain without seeing the traces on the under side of the board, but I am almost positive that the .01uF cap right above the inductor could be changed to a bigger value to get rid of the ear-piercing highs. You should try adjusting the pot rotation first though.


Here is a comparison of different wahs and their parts: http://www.aronnelson.com/gallery/main. ... alNumber=1
I bet it would be pretty straight forward to convert yours to any of these.

User avatar
fuzzbuzzfuzz
Breadboard Brother
Information
Posts: 58
Joined: 11 Dec 2009, 14:57
Has thanked: 1 time

Post by fuzzbuzzfuzz »

Ah thank you good info so far :)

I have posted some clearer shots of the insides and a shot of the reverse PCB traces, hopefully that may make things clearer.

http://fuzzbuzzfuzz.blogspot.com/2011/0 ... -guts.html

Thanks.

User avatar
iq01221
Solder Soldier
Information
Posts: 205
Joined: 18 Jun 2011, 16:17
Has thanked: 31 times
Been thanked: 8 times

Post by iq01221 »

:shock: I'm Juan from Argentina. I've just the same wah :hug: , and it's a nice italian wah for me. the only mod i've did to it is to "waxing" the inductor and add aluminum paper in the box. The caps in mine are diferent:
Image
Transistors are BC 547, the inductor is arround 480-510mH's( mi polimeter is not good at all, sorry 'bout that :oops: ).
And sounds great, well, I like it... :thumbsup

P/D: My english is a little crabby yet, ok? :oops:

User avatar
audioware
Information
Posts: 2
Joined: 17 Nov 2010, 23:58

Post by audioware »

I own this wha and it is exactly the same with yours.
It does have an inductor but all the schematics I could find are showing a design having 1 transistor and no inductor!!!
I have reverse-engineered the circuit and came up with a VOX clone http://www.freeinfosociety.com/electron ... php?id=617 ,
having some different component values.

Note that the 33K resistor which appears in the original VOX schematic, is ommited.
Attachments
Schematic
Schematic
Bespeco_Weeper.gif (15.55 KiB) Viewed 2225 times

User avatar
CHEEZOR
Diode Debunker
Information
Posts: 831
Joined: 10 Jul 2009, 18:19
Location: California
Has thanked: 42 times
Been thanked: 50 times

Post by CHEEZOR »

Nice. I was in the process of reversing it, but I didn't have time and was missing a couple values. I might just be blind at the moment, but I don't see any diode in the schematic... or the second electrolytic cap.

User avatar
iq01221
Solder Soldier
Information
Posts: 205
Joined: 18 Jun 2011, 16:17
Has thanked: 31 times
Been thanked: 8 times

Post by iq01221 »

The diode is just for protection, you cant just remove it, but if you don't, put it between +9V and ground. Easy :thumbsup ...

User avatar
audioware
Information
Posts: 2
Joined: 17 Nov 2010, 23:58

Post by audioware »

The schematic just shows the actual wha circuit and the values of the components.
I have omitted most of the other parts of the circuit, volume control and switching.
The cap is located next to the diode, there is also another cap (ceramic) missing.
I will update it soon.

User avatar
fuzzbuzzfuzz
Breadboard Brother
Information
Posts: 58
Joined: 11 Dec 2009, 14:57
Has thanked: 1 time

Post by fuzzbuzzfuzz »

Ah good - nice active thread! :D

So the the question is - any tweaks or mods that can be done to bring it up to spec or too make it sound a little sweeter and less harsh? Any caps or resistors that are fairly easy to switch out? If its a VOX clone which would be best, i certainly admire the sweet funky quack of the VOX :)

User avatar
pinkjimiphoton
Transistor Tuner
Information
Posts: 1242
Joined: 12 Sep 2010, 19:03
my favorite amplifier: my own, a redesigned princeton
Completed builds: so fucking many goddamn pedals it would make your ass hurt just looking at 'em all!!!!!
there's videos that totally suck of about 90 of 'em here:
http://youtube.com/666pinkster
gimme a like: http://facebook.com/pinkjimiphotonrocks
Location: new world order land (formerly la-la land)
Has thanked: 358 times
Been thanked: 479 times
Contact:

Post by pinkjimiphoton »

"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!

Post Reply